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1.
J Neural Transm (Vienna) ; 128(11): 1663-1675, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34333693

RESUMO

Cervical dystonia (CD) is a neurological movement disorder causing the neck to move involuntarily away from the neutral position. CD is a network disorder, involving multiple brain areas and, therefore, may impair movement in parts of the body other than the neck. This study used clinical assessments to investigate walking, balance and upper limb function (UL) in people with CD; the reliability of scoring these assessments and examined for relationship between CD severity, usual exercise and clinical assessments. We conducted a prospective observational cohort study of participants with isolated, focal, idiopathic CD. Participants were assessed by experienced physiotherapists and completed three questionnaires and eight clinical assessments of fear of falling, balance confidence, walking, balance, UL function and usual exercise. Results were compared to published data from healthy adults and other neurological populations. Twenty-two people with mild to moderate CD participated. Fear of falling, gross UL function and usual exercise were worse in people with CD compared with healthy adults, while walking, balance and distal UL function were similar to healthy populations. All assessments were reliably performed by physiotherapists, and we found no correlations between the severity of dystonia or usual exercise and performance on the physical assessments. Routine performance of clinical assessment of walking and balance are likely not required in people with mild to moderate CD; however, fear of falling and gross upper limb function should be assessed to determine any problems which may be amenable to therapy.


Assuntos
Torcicolo , Caminhada , Acidentes por Quedas , Adulto , Estudos Transversais , Medo , Humanos , Equilíbrio Postural , Estudos Prospectivos , Reprodutibilidade dos Testes , Extremidade Superior
2.
Clin Radiol ; 76(4): 316.e19-316.e28, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33551151

RESUMO

AIM: To evaluate the postoperative magnetic resonance imaging (MRI) findings of intracranial foreign body granulomas (FBGs) and true recurrent tumours (RTs) and thus lead to a basis for management decision-making. MATERIALS AND METHODS: Twenty-two patients with previous brain tumour surgery were diagnosed clinically with RT and underwent surgery. Re-operative pathology revealed FBG in eight patients and RT in 14 patients. MRI findings before the initial operation were compared to those before the re-operation. RESULTS: Features of FBGs versus RTs on MRI were as follows: (1) mean lesion size: 1.3 ± 0.7 (0.5-2.6) versus 3.2 ± 1.7 (1.1-6.3) cm (p=0.001, odds ratio [OR] = 4.18); (2) hypointensity on T2-weighted imaging (WI): 6/8 (75%) versus 0/14 (0%; p<0.001, OR=75.4); (3) non-restricted diffusion on diffusion-WI (DWI): 6/8 (75%) versus 2/14 (14.3%; p=0.008, OR=18); and (4) "ring and bubble" appearance on contrast-enhanced T1WI: 7/8 (87.5%) versus 2/14 (14.3%; p=0.001, OR=42). In comparison with their original tumours, the FBGs in the FBG group showed significantly lower T2 signal intensity, lower signal on DWI, and more cases of non-restricted diffusion on DWI (p=0.04, 0.04, 0.04, respectively). CONCLUSION: On brain MRI, FBGs can be differentiated from RTs by their relatively smaller size, hypointensity on T2WI, lack of restricted diffusion on DWI, and "ring and bubble" appearance on contrast-enhanced T1WI. Comparing the MRI findings of the focal lesion in the tumour bed with those of the original tumour is suggested to enhance diagnostic confidence.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Granuloma de Corpo Estranho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Criança , Pré-Escolar , Tomada de Decisão Clínica , Diagnóstico Diferencial , Feminino , Seguimentos , Granuloma de Corpo Estranho/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Complicações Pós-Operatórias/patologia , Reoperação , Adulto Jovem
3.
Acta Neurol Scand ; 127(1): 46-52, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22616889

RESUMO

OBJECTIVES: The long-term hemodynamic effects of carotid angioplasty and stenting (CAS) are unclear. We performed a longitudinal study to investigate the variations in cerebral hemodynamics in patients undergoing CAS. MATERIALS AND METHODS: We performed prospective evaluation of 63 symptomatic male patients (19 patients had transient ischemic attack and 44 had minor stroke; mean age: 77.3 ± 6.3 years [range: 51-86]). The mean blood flow velocities (MBFV) and pulsatility index (PI) of the middle cerebral arteries (MCA) on both sides were evaluated using transcranial color-coded Doppler (TCCD) ultrasonography. Cardiac autonomic activities were evaluated by measuring baroreflex sensitivity (BRS). All parameters were measured at baseline prior to CAS and at 1, 3, 6, and 12 months after CAS. RESULTS: The preoperative MBFV and PI of the ipsilateral MCA were significantly lower than those of the contralateral side. However, after CAS, MBFV in the ipsilateral MCA increased significantly until 2 weeks after stenting, after which the MBFV gradually decreased and remained stable for 1 year after CAS. Further, we observed a nonsignificant increase in MBFV in the contralateral MCA after CAS. In contrast to the MBFV, the BRS values decreased significantly 1 month after stenting and returned to baseline levels 6 months after CAS. CONCLUSIONS: Patients with CAS showed improved global cerebral hemodynamic status. However, the BRS did not normalize initially, and baseline value was achieved at 6 months after stenting.


Assuntos
Barorreflexo/fisiologia , Estenose das Carótidas/patologia , Estenose das Carótidas/fisiopatologia , Córtex Cerebral/irrigação sanguínea , Hemodinâmica , Stents , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Angiografia Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Estudos Prospectivos , Acidente Vascular Cerebral/cirurgia , Taiwan , Fatores de Tempo , Ultrassonografia Doppler Transcraniana
4.
Clin Radiol ; 68(11): e561-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23835404

RESUMO

AIM: To evaluate factors related to the technical and haemostatic outcomes of endovascular management in patients with head and neck cancers (HNC) associated with carotid blowout syndrome (CBS) of the external carotid artery (ECA). MATERIALS AND METHODS: Between 2002 and 2011, 34 patients with HNC with CBS involving branches of the ECA underwent endovascular therapy. Treatment included embolization with microparticles, microcoils, or acrylic adhesives. Fisher's exact test was used to examine demographic features, clinical and angiographic severities, and clinical and imaging findings as predictors of endovascular management outcomes. RESULTS: Technical success and immediate haemostasis were achieved in all patients. Technical complications were encountered in one patient (2.9%). Rebleeding occurred in nine patients (26.5%). Angiographic vascular disruption grading from slight (1) to severe (4) revealed that the 18 patients with acute CBS had scores of 2 (2/18, 11.1%), 3 (3/18, 16.7%), and 4 (13/18, 72.2%). The 16 patients with impending and threatened CBS had scores of 1 (1/16, 6.25%), 2 (5/16, 31.25%), and 3 (10/16, 62.5%; p = 0.0003). For the 25 patients who underwent preprocedural computed tomography (CT)/magnetic resonance imaging (MRI) examinations within 3 months of treatment, the agreement between clinical and imaging findings reached the sensitivity, specificity, and kappa values for recurrent tumours (1, 0.7143, 0.7826), soft-tissue defect (0.9091, 0.3333, 0.2424), and sinus tract/fistula (0.4737, 0, 0.4286). CONCLUSION: Endovascular management for patients with CBS of the ECA had high technical success and safety but was associated with high rebleeding rates. We suggest applying aggressive post-procedural follow-up and using preprocedural CT/MRI to enhance the periprocedural diagnosis.


Assuntos
Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/terapia , Artéria Carótida Externa/diagnóstico por imagem , Artéria Carótida Externa/patologia , Embolização Terapêutica/métodos , Neoplasias de Cabeça e Pescoço/complicações , Adulto , Idoso , Meios de Contraste , Feminino , Seguimentos , Humanos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ruptura Espontânea/complicações , Ruptura Espontânea/terapia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
5.
Dystonia ; 22023.
Artigo em Inglês | MEDLINE | ID: mdl-37920445

RESUMO

According to expert consensus, dystonia can be classified as focal, segmental, multifocal, and generalized, based on the affected body distribution. To provide an empirical and data-driven approach to categorizing these distributions, we used a data-driven clustering approach to compare frequency and co-occurrence rates of non-focal dystonia in pre-defined body regions using the Dystonia Coalition (DC) dataset. We analyzed 1,618 participants with isolated non-focal dystonia from the DC database. The analytic approach included construction of frequency tables, variable-wise analysis using hierarchical clustering and independent component analysis (ICA), and case-wise consensus hierarchical clustering to describe associations and clusters for dystonia affecting any combination of eighteen pre-defined body regions. Variable-wise hierarchical clustering demonstrated closest relationships between bilateral upper legs (distance = 0.40), upper and lower face (distance = 0.45), bilateral hands (distance = 0.53), and bilateral feet (distance = 0.53). ICA demonstrated clear grouping for the a) bilateral hands, b) neck, and c) upper and lower face. Case-wise consensus hierarchical clustering at k = 9 identified 3 major clusters. Major clusters consisted primarily of a) cervical dystonia with nearby regions, b) bilateral hand dystonia, and c) cranial dystonia. Our data-driven approach in a large dataset of isolated non-focal dystonia reinforces common segmental patterns in cranial and cervical regions. We observed unexpectedly strong associations between bilateral upper or lower limbs, which suggests that symmetric multifocal patterns may represent a previously underrecognized dystonia subtype.

6.
Acta Neurol Scand ; 123(3): 187-92, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20569227

RESUMO

OBJECTIVE: Percutaneous carotid angioplasty and stenting (CAS) has been used to improve cerebral circulation and autoregulation. However, whether CAS ameliorates the autonomic regulatory dynamics remains unclear. This prospective study examines the neurocardiovascular dynamics following carotid stenting. METHODS: Thirty minutes electrocardiograms were recorded at three different time points (pre-operative, 1-h post-operative, 1-day post-operative) on twelve male patients (mean age 70.8 ± 9.6 years) receiving unilateral primary CAS. The HR data were analyzed by the conventional heart rate variability (HRV) and the multiscale entropy (MSE) methods; the former associates with autonomic activities and the latter quantifies the regulatory complexity of heart beat intervals. Loss of complexity at multiple scales has been associated with decoupled regulatory network in vivo. RESULTS: Conventional HRV indices showed no difference after CAS. Complexity indices increased significantly on scales 2-8 at 1-h and on scales 2-3 1-day post-treatment. The lower scale MSE (1-5) correlated with the frequency components of conventional HRV indices. The increased complexity could imply a restoration of the neurocardiovascular dynamics on the path to a healthier state. CONCLUSIONS: Primary CAS can induce a recovery in the neurocardiovascular regulatory dynamics in patients with high-grade carotid stenosis.


Assuntos
Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/terapia , Stents , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Angioplastia/métodos , Estenose das Carótidas/diagnóstico , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico/métodos , Projetos Piloto , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia
7.
Acta Neurochir (Wien) ; 152(2): 321-4, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19377848

RESUMO

We report a patient with traumatic carotid-cavernous fistula associated with an isolated internal carotid artery in whom, after trans-arterial balloon embolisation, premature balloon detachment occurred with balloon migration to the supraclinoid carotid artery, leading to total occlusion of the blood flow. The carotid flow was eventually restored by direct puncture of the detached balloon via the optic canal and by deploying a coronary stent to fix the balloon in the vascular wall. The fistula was eventually occluded by using detachable coils. He was discharged with a mild hemiparesis and decreased acuity in the left eye.


Assuntos
Oclusão com Balão/efeitos adversos , Lesões das Artérias Carótidas/etiologia , Fístula Carótido-Cavernosa/cirurgia , Migração de Corpo Estranho/etiologia , Complicações Intraoperatórias/etiologia , Instrumentos Cirúrgicos/efeitos adversos , Acidentes de Trânsito , Adulto , Angioplastia/instrumentação , Angioplastia/métodos , Anticoagulantes/uso terapêutico , Oclusão com Balão/instrumentação , Oclusão com Balão/métodos , Lesões das Artérias Carótidas/patologia , Lesões das Artérias Carótidas/fisiopatologia , Artéria Carótida Interna/patologia , Artéria Carótida Interna/fisiopatologia , Artéria Carótida Interna/cirurgia , Estenose das Carótidas/etiologia , Estenose das Carótidas/patologia , Estenose das Carótidas/cirurgia , Fístula Carótido-Cavernosa/etiologia , Fístula Carótido-Cavernosa/patologia , Angiografia Cerebral , Migração de Corpo Estranho/patologia , Migração de Corpo Estranho/fisiopatologia , Humanos , Doença Iatrogênica/prevenção & controle , Complicações Intraoperatórias/patologia , Complicações Intraoperatórias/fisiopatologia , Masculino , Motocicletas , Inibidores da Agregação Plaquetária/uso terapêutico , Reoperação , Osso Esfenoide/anatomia & histologia , Osso Esfenoide/cirurgia , Stents , Resultado do Tratamento
8.
Water Sci Technol ; 62(7): 1689-93, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20935389

RESUMO

This study investigated the feasibility of reusing wastewater sludge ash in construction materials to replace partial materials. Wastewater sludge sampled from thermal power plant was burned into sludge ash at 800°C in the laboratory. The sludge incineration ash has low heavy metal including Pb, Cd, Cr and Cu, so it belongs to general enterprise waste. The chemical composition of sludge incineration ash was summed up in SiO2, CaO, Fe2O3 and MgO. Then the wastewater sludge ash is also found to be a porous material with irregular surface. When the sludge ash was used to replace mortar or concrete cement, its water-adsorption capability will result in the reduction of mortar workability and compressive strength. Cement is being substituted for sludge ash, and 10 percent of sludge ash is more appropriate. Sludge ash is reused to take the place of construction materials and satisfies the requests of standard specification except for higher water absorption.


Assuntos
Materiais de Construção , Esgotos , Força Compressiva , Teste de Materiais
9.
Int J Oral Maxillofac Surg ; 49(10): 1254-1259, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32007356

RESUMO

Cleft lip and/or cleft palate are the most common congenital craniofacial anomalies. Philtral ridge morphology is an important aesthetic component of unilateral cleft lip (UCL) repair. To this end, we have developed two techniques of philtral ridge reconstruction: (1) asymmetric mattress muscle sutures, and (2) overlapping mattress muscle sutures. The objective of this retrospective cohort study was to compare their outcomes in UCL repairs. Group I patients (n=30) underwent UCL repair before August 2003, including philtral ridge reconstruction by asymmetric mattress muscle sutures. Group II patients (n=30) underwent UCL repair after August 2003, including philtral ridge reconstruction by overlapping mattress muscle sutures. Philtral morphology was evaluated by ultrasonographic and three-dimensional photographic measurements, examining cleft side philtral projection and philtral ridge symmetry. These demonstrated that group II patients had better philtral column symmetry and projection on the cleft side when compared to group I. Overlapping mattress muscle sutures produced better philtral morphology in UCL repairs than asymmetric mattress muscle sutures.


Assuntos
Fenda Labial , Procedimentos de Cirurgia Plástica , Fenda Labial/diagnóstico por imagem , Fenda Labial/cirurgia , Músculos Faciais/cirurgia , Humanos , Lábio/cirurgia , Estudos Retrospectivos
10.
AJNR Am J Neuroradiol ; 40(3): 540-542, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30679218

RESUMO

Time-density curve analysis of DSA provides useful blood flow information. However, manually selecting the ROI is time-consuming. We developed an automatic technique to provide arterial, capillary, and venous vasculatures with corresponding time-density curves. This study retrospectively analyzed the data of 36 patients with unilateral carotid stenosis. We found that the full width at half maximum of the time-density curve for the automatically segmented capillary vasculature is a suitable representation of the cerebral circulation time.


Assuntos
Angiografia Digital/métodos , Estenose das Carótidas/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Tob Control ; 17(3): 183-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18522971

RESUMO

OBJECTIVE: This study assesses the effects of a 2005 increase in funding for smoking cessation services on provider participation, patient utilisation of smoking cessation services and cessation outcome at a six-month follow-up. METHODS: Analyses are based on existing databases and on a follow-up study among smokers participating in the smoking cessation service. The effect of the policy is evaluated by comparing year 2004 (old policy) with year 2005 (new policy). The generalised estimating equations (GEE) method was conducted to examine the effects of increasing funding for smoking cessation services on monthly smoking cessation services provided per physician and yearly consultations received per patient. Logistic regression was used to examine the effects of increasing funding on smoking cessation outcome. RESULTS: The study found the increased reimbursement rates and medication subsidies for smoking cessation to be positively related to the number of physicians enrolling in the programme (1841 in 2004 vs 3466 in 2005), the number of cessation consultations per month per physician (5.1 vs 14.6) and the number of cessation visits per year per patient (2.0 vs 2.5). Male providers and providers belonging to the private sector were found to offer more cessation consultations. The number of subjects receiving this counselling increased from 22 167 in 2004 to 109 508 in 2005. After adjusting for consumer and provider factors the likelihood of successful quitting among those counselled did not change. Overall, smokers who were older, had attempted to quit in the past year, had lower nicotine dependence, had gone to more smoking cessation service visits, had received consultations in the public sector and were seen by physicians delivering fewer consultations were more likely to have quit smoking at the six-month follow-up. CONCLUSIONS: Based on increases in physician enrollment and consultations and the increase in number of subjects receiving counselling and number of visits, the policy of increasing provider incentives and medication subsidies appears to have successfully promoted smoking cessation services.


Assuntos
Assistência Ambulatorial/economia , Padrões de Prática Médica/economia , Abandono do Hábito de Fumar/economia , Adolescente , Adulto , Idoso , Assistência Ambulatorial/estatística & dados numéricos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta/estatística & dados numéricos , Reembolso de Incentivo/economia , Taiwan
12.
Cephalalgia ; 27(12): 1413-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17888012

RESUMO

Spontaneous intracranial hypotension (SIH) associated with subarachnoid haemorrhage (SAH) has never been reported. Here, we report on a case of a 33-year-old woman with SIH, who developed simple partial sensory seizures 3 weeks later. Neuroimaging studies, including brain computed tomography and angiography, were initially normal, but revealed an isolated cortical venous thrombosis at 3 weeks. One week later, brain magnetic resonance imaging showed SAH around the thrombosed cortical vein. We postulate that the decline in the venous blood flow velocity due to SIH may have resulted in cortical venous thrombosis, which in turn led to rupture of the vessel wall and SAH in this patient.


Assuntos
Veias Cerebrais/patologia , Transtornos Cerebrovasculares/diagnóstico , Hipotensão Intracraniana/diagnóstico , Convulsões/diagnóstico , Hemorragia Subaracnóidea/diagnóstico , Trombose Venosa/diagnóstico , Adulto , Transtornos Cerebrovasculares/complicações , Feminino , Humanos , Hipotensão Intracraniana/complicações , Convulsões/complicações , Hemorragia Subaracnóidea/complicações , Trombose Venosa/complicações
13.
AJNR Am J Neuroradiol ; 28(1): 181-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17213454

RESUMO

BACKGROUND AND PURPOSE: Some reports of reconstructive management of carotid blowout syndrome (CBS) with stent-grafts are promising, but some are unfavorable. This study sought to evaluate the hemostatic efficacy, safety, and outcome of reconstructive, endovascular stent-graft placement in patients with head-and-neck cancers in association with CBS. METHODS: Eight patients with head-and-neck cancers with CBS were treated with self-expandable stent-grafts. We evaluated the initial hemostatic results, complications, and outcomes by assessing the clinical and imaging findings. RESULTS: Immediate hemostasis was achieved in all patients. Initial complications included stroke in 1 patient and asymptomatic thrombosis of the carotid artery in 2 patients. Delayed complications included rebleeding, delayed carotid thrombosis, and brain abscess formation. Rebleeding was noted in 4 patients and was successfully managed with a second stent-graft and embolization in 2 of them. Delayed carotid thrombosis with follow-up after 3 months was found in 3 patients, 1 of whom had associated brain abscesses. CONCLUSION: Although stent-grafts achieved immediate and initial hemostasis in patients with head-and-neck cancers and CBS, long-term safety, stent patency, and permanency of hemostasis appeared unfavorable. This treatment may be for temporary or emergency purposes rather than serving as a permanent measure. We suggest its applications in patients with acute CBS that precludes performance of an occlusion test, as well as when carotid occlusion poses an unusually high risk of neurologic morbidity. We also propose prophylactic antibiotic treatment and combined embolization of pathologic vascular feeders to improve outcomes.


Assuntos
Falso Aneurisma/terapia , Angioplastia com Balão/métodos , Implante de Prótese Vascular/métodos , Doenças das Artérias Carótidas/terapia , Emergências , Hemorragia/terapia , Técnicas Hemostáticas , Neoplasias Otorrinolaringológicas/complicações , Stents , Doença Aguda , Adulto , Idoso , Falso Aneurisma/diagnóstico , Falso Aneurisma/etiologia , Artérias Carótidas/patologia , Artérias Carótidas/efeitos da radiação , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/etiologia , Terapia Combinada/efeitos adversos , Diagnóstico por Imagem , Feminino , Seguimentos , Hemorragia/diagnóstico , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Otorrinolaringológicas/diagnóstico , Neoplasias Otorrinolaringológicas/terapia , Lesões por Radiação/complicações , Lesões por Radiação/diagnóstico , Lesões por Radiação/terapia , Fatores de Risco
14.
Mol Cell Biol ; 21(12): 3935-46, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11359901

RESUMO

Some patients with B-cell-negative severe combined immune deficiency (SCID) carry mutations in RAG-1 or RAG-2 that impair V(D)J recombination. Two recessive RAG-1 mutations responsible for B-cell-negative SCID, R621H and E719K, impair V(D)J recombination without affecting formation of single-site recombination signal sequence complexes, specific DNA contacts, or perturbation of DNA structure at the heptamer-coding junction. The E719K mutation impairs DNA cleavage by the RAG complex, with a greater effect on nicking than on transesterification; a conservative glutamine substitution exhibits a similar effect. When cysteine is substituted for E719, RAG-1 activity is enhanced in Mn(2+) but remains impaired in Mg(2+), suggesting an interaction between this residue and an essential metal ion. The R621H mutation partially impairs nicking, with little effect on transesterification. The residual nicking activity of the R621H mutant is reduced at least 10-fold upon a change from pH 7.0 to pH 8.4. Site-specific nicking is severely impaired by an alanine substitution at R621 but is spared by substitution with lysine. These observations are consistent with involvement of a positively charged residue at position 621 in the nicking step of the RAG-mediated cleavage reaction. Our data provide a mechanistic explanation for one form of hereditary SCID. Moreover, while RAG-1 is directly involved in catalysis of both nicking and transesterification, our observations indicate that these two steps have distinct catalytic requirements.


Assuntos
Rearranjo Gênico do Linfócito B , Proteínas de Homeodomínio/genética , Mutação , Recombinação Genética , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Linfócitos B/imunologia , Sequência de Bases , Cátions Bivalentes , Linhagem Celular , DNA/metabolismo , Primers do DNA/genética , Esterificação , Humanos
15.
J Mol Neurosci ; 30(1-2): 129-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17192658

RESUMO

Although the in vitro effect of organophosphorus (OP) compounds on acetylcholine-esterase (AChE) has been studied extensively, the hypothesis that OP inhibition of AChE is the primary mechanism of acute in vivo OP toxicity has been controversial. For example, a recent review (Pope and Liu, 2004) suggested that OP compounds have direct toxic effects on other enzymes, ACh receptors, and receptor/ channel complexes that are independent of AChE inhibition. The purpose of this report is to examine the hypothesis that AChE inhibition is the mechanism of acute toxicity of OP compounds by mathematically modeling the in vivo lethal effects of highly toxic OP compounds and determining the amount of variation in OP toxicity that is explained by AChE inhibition.


Assuntos
Inibidores da Colinesterase/toxicidade , Organofosfatos/toxicidade , Animais , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Dose Letal Mediana , Oximas/toxicidade
16.
AJNR Am J Neuroradiol ; 27(7): 1535-40, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16908575

RESUMO

BACKGROUND AND PURPOSE: Transarterial detachable balloon embolization of direct carotid cavernous fistulas (DCCFs) has become an optimal treatment. In a few cases, the parent artery has to be sacrificed to achieve morphologic cure. We present our experience with transarterial balloon-assisted n-butyl-2-cyanoacrylate (n-BCA) embolization of DCCFs in which there was failure to achieve angiographic cure and preservation of parent arteries. METHODS: Of 141 patients with traumatic DCCFs who had been treated by transarterial embolization with occlusion of the fistula and parent artery preservation, 18 received transarterial balloon-assisted n-BCA embolization-6 for residual fistula after the balloons detached, 7 for recurrent fistula because of premature balloon deflation or migration, and 5 for repeated puncture of the detachable balloon by the bony fragment at the cavernous sinus. A total of 27 procedures were performed with an average 1.5 attempts per patient, and the volume of the n-BCA mixture varied from 0.5 to 2.3 mL with a mean of 0.83 mL. RESULTS: All DCCFs were successfully occluded by the n-BCA mixture with preservation of parent arteries. One patient with a giant cavernous sinus varix had a fatal subarachnoid hemorrhage. One had a recurrence and was treated by internal carotid artery (ICA) occlusion. Five had asymptomatic pseudoaneurysms at the parent artery. There was no adhesion of the n-BCA mixture to the protective balloon or the microcatheter or n-BCA reflux into the parent arteries. CONCLUSION: Transarterial balloon-assisted n-BCA embolization is a feasible, efficient, and safe treatment for DCCFs when angiographic cure and ICA preservation are not achieved by transarterial detachable balloon embolization.


Assuntos
Fístula Carótido-Cavernosa/terapia , Cateterismo/métodos , Embolização Terapêutica/métodos , Embucrilato/uso terapêutico , Adesivos Teciduais/uso terapêutico , Adulto , Falso Aneurisma/etiologia , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/patologia , Fístula Carótido-Cavernosa/diagnóstico por imagem , Embolização Terapêutica/instrumentação , Embucrilato/administração & dosagem , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Recidiva , Retratamento , Segurança , Hemorragia Subaracnóidea/etiologia , Adesivos Teciduais/administração & dosagem , Resultado do Tratamento , Varizes/terapia
17.
AJNR Am J Neuroradiol ; 27(7): 1543-5, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16908577

RESUMO

A patient with hypopharyngeal cancer developed carotid blowout syndrome (CBS) treated by self-expandable stent-graft in the left carotid artery. CT scan for progressive right hemiparesis 4 months later showed multiple left cerebral abscesses and left carotid thrombosis. Although deployment of stent-grafts for CBS can achieve initial hemostasis in patients with head-and-neck cancer, the placement of a stent-graft in a field of necrosis and infection is associated with poor long-term outcome. We recommend the use of prophylactic antibiotics if endovascular foreign materials are placed in a contaminated field.


Assuntos
Falso Aneurisma/terapia , Prótese Vascular/efeitos adversos , Abscesso Encefálico/etiologia , Doenças das Artérias Carótidas/terapia , Artéria Carótida Interna/patologia , Infecções Relacionadas à Prótese/etiologia , Stents/efeitos adversos , Carcinoma de Células Escamosas/radioterapia , Artérias Carótidas/efeitos da radiação , Trombose das Artérias Carótidas/etiologia , Artéria Carótida Primitiva/patologia , Seguimentos , Humanos , Neoplasias Hipofaríngeas/radioterapia , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/terapia
19.
Nucleic Acids Res ; 28(14): 2695-701, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10908325

RESUMO

Messenger RNAs (mRNAs) that contain U-rich elements are targeted for rapid decay. Selective inhibition of this decay results in a rapid increase in steady state level. Thus, this is an important regulatory step in gene expression. Previously, we have found that these mRNAs are selectively stabilized by a specific mRNA binding protein called HuR. The mechanism of action of HuR is not well understood. It has been postulated that HuR stabilizes mRNA by the displacement or inhibition of factors that specifically cleave or deadenyl-ate these mRNAs. In this paper, we report the identification and characterization of a novel endo-nuclease that cleaves within an HuR binding site in p27kip1 mRNA. The specificity of this endonuclease and its inhibition by HuR argue for it playing a role in the postranscriptional regulation of gene expression.


Assuntos
Antígenos de Superfície , Endonucleases/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sequência de Bases , Sítios de Ligação , Proteínas ELAV , Proteína Semelhante a ELAV 1 , Endonucleases/antagonistas & inibidores , Células HeLa , Humanos , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/farmacologia , Especificidade por Substrato
20.
J Clin Neurosci ; 29: 180-2, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26916904

RESUMO

Orthostatic unsteadiness (unsteadiness on standing) is a relatively common symptom and can have neurological or non-neurological causes. Glass et al. have recently described a syndrome presenting with unsteadiness or leg jerking during standing or gait initiation difficulty which they have termed orthostatic myoclonus (OM). OM is a disabling syndrome but potentially treatable. It may develop on the background of neurodegenerative disease; other causes include pro-myoclonic drugs such as tricyclic antidepressants. In order to increase awareness of this syndrome, we report four patients with electrophysiologically confirmed OM who were referred to the movement disorder unit for lower limb tremor studies. All four patients presented with unsteadiness on standing. There were no signs suggestive of neurodegenerative disease and three of the patients had a provisional diagnosis of orthostatic tremor. The diagnosis of OM was supported by a surface electromyography showing 9-16Hz, non-rhythmic muscle bursts with burst duration of 50-100ms during standing. OM is unrecognised by many physicians as a cause of orthostatic intolerance. The most common syndrome with which OM may be confused is orthostatic tremor. A correct diagnosis is important as it may respond to treatment with clonazepam, gabapentin or piracetam.


Assuntos
Mioclonia/diagnóstico , Intolerância Ortostática/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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